Adsorption of nitrobenzene, aniline and nitroanilines on the surface of a basal face of graphite

Thermodynamic characteristics of the adsorption of nitrobenzene, aniline, and isomeric nitro-anilines are determined experimentally and from molecular statistics in the range of the closest packing of a graphite surface according to equilibrium gas adsorption chromatography. It is found that graphitized thermal carbon black is characterized by high selectivity upon the chromatographic separation of isomeric nitro-anilines (retention increases in the series of ortho, meta, and para isomers). Using the atom-atomic approximation of the semi-empirical molecular statistical theory of adsorption, parameters are calculated for the potential function of the pair intermolecular interaction of the NO₂ group in nitrobenzene and the N atom in aniline with the C atoms in a basal face of graphite. The effect of the NH₂ and NO₂ groups on the parameters of adsorption for isomeric nitroanilines as a result of direct polar conjugation is demonstrated and must be assumed when performing molecular statistical calculations.